Mycobacterium Ulcerans Infection and Buruli Ulcer Dynamics

Mycobacterium ulcerans is an environmental bacterium responsible for Buruli ulcer, a necrotising disease of skin and subcutaneous tissue. The pathogen secretes mycolactone, a lipid toxin that induces tissue necrosis and local immunosuppression, allowing the bacterium to multiply in a largely acellular environment. Buruli ulcer predominantly affects rural and peri-urban communities in West and Central Africa, but foci also exist in South-east Australia and parts of South America. Human infection is acquired through poorly understood environmental exposures, with evidence pointing to insect bites, minor skin trauma and contact with contaminated water or soil. Clinical presentation ranges from painless nodules and plaques to large ulcers that may lead to permanent scarring, deformity or functional impairment if untreated. Current management relies on combined antibiotic therapy, wound care and, when necessary, surgical intervention. Control efforts require a clearer understanding of ecological reservoirs, transmission pathways and host factors governing susceptibility and healing. Recent studies have begun to delineate the role of wildlife reservoirs, insect vectors and host immune responses, contributing to more targeted prevention strategies and improved diagnostic and therapeutic approaches.

Research from Nature Portfolio

Recent studies have traced the transmission of M. ulcerans in southeastern Australia to a wildlife–vector cycle involving possums and mosquitoes. Field surveys detected M. ulcerans DNA in possum excreta and in Aedes notoscriptus populations, with spatial clustering of positive mosquitoes, possum faeces and human cases. Metabarcoding of blood meals demonstrated that the same mosquitoes had fed on both possums and humans. Genomic comparison of bacterial isolates from possums, mosquitoes and patients revealed shared single-nucleotide-polymorphism profiles, confirming that mosquitoes act as mechanical vectors. These findings underline the importance of integrated vector management alongside environmental surveillance to prevent Buruli ulcer outbreaks.

Mycobacterium Ulcerans Infection and Buruli Ulcer Dynamics publication trend

The graph below shows the total number of articles in mycobacterium ulcerans infection and buruli ulcer dynamics across all publications each year (not limited to Nature Index journals).

Technical terms

Mycolactone: A polyketide-derived toxin produced by M. ulcerans that causes tissue necrosis and immunosuppression.

Vector: An organism, such as a mosquito, that mechanically or biologically transmits a pathogen between hosts.

Reservoir: A species or environmental niche in which a pathogen normally lives and multiplies, serving as a source of infection.

Innate immune tolerance: A state in which innate immune cells display reduced inflammatory responses upon repeated exposure to a pathogen or its products.

Single-nucleotide polymorphism (SNP): A variation of a single base pair in the genome, used to differentiate strains of a microorganism.

Case–control study: An observational epidemiological design comparing individuals with a disease (cases) to similar individuals without the disease (controls) to identify risk and protective factors.

References

1. Mosquitoes provide a transmission route between possums and humans for Buruli ulcer in southeastern Australia. Nature Microbiology (2024).
2. Type-I interferons promote innate immune tolerance in macrophages exposed to Mycobacterium ulcerans vesicles. PLOS Pathogens (2023).
3. Comprehensive Case–Control Study of Protective and Risk Factors for Buruli Ulcer, Southeastern Australia - Volume 29, Number 10—October 2023 - Emerging Infectious Diseases journal - CDC. Emerging Infectious Diseases (2023).
4. What about Current Diversity of Mycolactone-Producing Mycobacteria? Implication for the Diagnosis and Treatment of Buruli Ulcer. International Journal of Molecular Sciences (2023).